Originally Posted by
bryroth
Someone once told me that unless the wires on the V brakes ...
I'm assuming this is a typo, as the first post mentions cantilever brakes. If it isn't a typo be aware that cantis and v-s require different levers (or an adapter) to get the right amount of cable pull to function well on the bike.
Originally Posted by
bryroth
Someone once told me that unless the wires on cantis are at a perfect 90-degree angle from each other then it can be dangerous. Is that correct?
Not at all. There are several angles in a canti set up that varies as brakes are activated, pads wear and parts flex, so don't worry about it. There is a "perfect" angle to aim for, but the "spot of optimum performance" is surrounded by a rather wide zone of "perfectly acceptable performance".
The only proposed danger that I know of is that a low-set straddle cable can get caught in the tire tread and cause an endo if the main brake cable should break.
Originally Posted by
bryroth
Also, I'm thinking about buying fat tires for my cyclocross bike. Seems like you are saying that even fat tires, like going from a 37 from a 27, will have the same or a comparable size rim? I had assumed that the rim size would increase proportionally.
Rims come in far less different widths than tires do, and going up or down a size or two usually works just fine.
See
http://sheldonbrown.com/tire-sizing.html for more.
Short quote:
A general guideline is that the tire width should be between 1.45/2.0 x the inner rim width.
If you flatten out a tire and measure the total width from bead to bead, it should be approximately 2.5 x the ISO width.
If your tire is too narrow for the rim there's an increased risk of tire/rim damage from road hazards.
If its too wide for the rim, there's an increase risk of sidewall wear, and a greater risk of loss of control in the event of a sudden flat.
CX bikes generally have quite good frame/tire clearance, but I'd be more concerned about that than the rim anyhow.